Termín přednášky: 26.11.2013 v 15:00
Místo konání: Zasedací místnost děkanátu FEL (EU 219)
Přednášející: Prof. DR. Roland SCHIEK (University of Aplied Science, Regensburg (D))
In crystals with quadratic nonlinearity typical cubic nonlinear effects are observed at power levels below the values corresponding to the cubic material susceptibility. Responsible is a cascading of quadratic nonlinearities which mimicks a cubic nonlinearity and produces typical cubic nonlinear diffractive effects yielding intensity-dependent wave propagation. Amplitude and phase of femto and picosecond pulses propagating in lithium niobate waveguides were retrieved from FROG-spectrograms. The well-known self-phase modulation in fibers was now measured in integrated optics. Dependent on the phase-mismatch of the quadratic nonlinear interaction self-phase modulation can be adjusted in sign and value. Typical related effects like soliton propagation and switching were observed. The measurements were very well explained by theory and were used to extract the nonlinear coefficients of lithium niobate.
Přednáška je podpořena z projektu SPPVaV – Systematická podpora popularizace výzkumu a vývoje ZČU, reg. č. CZ.1.07/2.3.00/35.0014.